PROJECT SUMMARY Background: The purpose of this study is to directly address Special Interest Notification NOT-HS-16-011, Innovative Research in Primary Care, by examining the impact of team configuration, team stability, and role stability on clinical performance in primary care team settings. The Joint Principles of the Patient Centered Medical Home (PCMH) recommend a team-based approach to primary care to ensure that patients receive high- quality, well-coordinated care from a consistent team of health-care professionals. However, real-world implementation of the Joint Principles often deviates significantly from the Principles' propositions. Though the science of what makes teams effective is well documented, far less is known about the impact specific configurations may have on teams' ability to deliver care effectively. This study leverages a unique data source from the Veterans Health Administration (VHA) containing one of the largest, most diverse national samples of primary care teams to examine team configuration factors through the lens of social network analysis. Specific Aims: (1) Select a targeted set of clear, measurable, accountable, primary care performance metrics, prioritized according to their overall contribution and value to primary care. (2) Determine the impact of team configuration on primary care clinical performance as measured in Aim 1. (3) Determine the impact of team stability and specific role stability on clinical performance as measured in Aim 1. Methods: In Aim 1 we will convene a 10-member expert panel representing relevant key stakeholder groups, including primary care team members, administrators, scientists, and patients. Drawing from existing sources of clinical performance metrics, the panel will select and prioritize a targeted set of primary care performance measures, which will be used as the primary outcomes in Aims 2 and 3. The process will be facilitated using key elements of the Productivity Measurement and Enhancement System (ProMES), a comprehensive, evidence- based methodology from industrial/organizational psychology for developing and implementing performance measurement systems. Aims 2 and 3 will consist of a database review of a sample of approximately 7,700 primary care teams from 1200 VHA healthcare locations throughout the United States. We will link multiple data sources from VHA (Team Assignments Report, HR Smart, VHA Corporate Data Warehouse) to create a dataset with measures of clinical performance, team configuration, team stability, role stability, and adherence to recommended team configurations for all teams in our sample. Team configuration variables will be computed via social network analysis. Hierarchical linear models will be conducted to test the hypotheses that higher clinical performance scores are more likely to be observed in teams (a) who adhere more closely to recommended team configurations (b) that are more stable over time, and (c) whose clinical manager role is more stable over time.